Cooling system for internalcombustion engines



July 2, 1946. I w HANNERs 2,403,218

COOLING SYSTEM FOR INTERNAL-COMBUSTION ENGINES Filed Nov. 24, 1944 2 Sheets-Sheet 1' 0 0') cum FLOW NSATE RETURN 51- M J/ WATER S g 7/; 2 z I Lmj- O N 9 j N 1 7 N 9 a r\ 3 w I INVENTOR.

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H. W. 'HANNERS COOLING SYSTEM FOR INTERNAL-COMBUSTION ENGINES Filed Nov. 24, 1944 2 Sheets-Sheet 2 VAPOR ENTERS v CONDENSATIE RETURN v VAPOR ENTERS :HERE.

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. ,fl z yddl$nxzerzn hTTQEHEY of my invention in its Patented July 2, 1946 UNITED STATES PATENT OFFICE COOLING SY SIEM FOR INTERNAL- COMBUSTION ENGINES Harvey W. Banners, Springfield, Ohio, assignor to The National Supply Company,

lvanla Pittsburgh,

Pa., a corporation of Pennsy Application November 24, 1944, Serial No. 564,983

3 Claims. 01. 123-114) covering any coolant capable of being used in the system. The system is designed to operate by the boiling and condensing cycle. the excess heat being discharged into the atmosphere while the coolant medium merely acts as a carrier for the waste heat from the cylinders to the discharging means and is circulated through the,

system by the well known thermo-sy hon system. My device is adaptable to any type of internal combustion engine but for the purpose of illustration is shown as applied for use in connection with the horizontal type.

An object of my invention is to provide a coolingsystem for internal combustion engines based upon a combination of the therm'o-syphon and vapor phase cooling which is free from hot spots in the engine jackets and cold spots at the point of condensate return.

Another principal object of my invention is to provide a vapor cooling system for an internal combustion engine wherein a water circulating passageway is formed wholly within the jacket chamber and is in unobstructed communication at both its upper and lower ends directly into the said jacket chamber to prevent cold spots in the Another object is to provide a double pass radiator in the above mentioned system wherein the first or primary radiator acts in the capacity of a down flow condenser while the second radiator acts as a secondary condenser toextract the last trace of water vapor from the'entrapped moisture laden air. 7

Other important features consist in the arrangement of the system as hereinafter described and claimed.

In the accompanying drawings 1 have illustrated a cooling system embodying the features preferred form wherein,

Fig. 1 is a side elevation of a portion of an internal combustion engine equipped with my improved cooling system.

Fig. 2 is an end elevation of Fig. 1, partly in section taken along the line 2-2 of'Flg. 1 showing the location of the filler neck.

Fig. 3 is a front elevation of one form of a double pass radiator used with my invention.

Fig. 4 is an end elevation of the radiator shown in ms. 3.

Fig. 5 is a front elevation of an alternate construction of a single pass radiator adapted to be used with my invention.

coolant chamber.

Fig. 6 is an end elevation of the radiator shown in Fig. 5.

WATER CIRGUIA'I'IOR C10 The circulating cooling system about to be described in the preferred embodiment of my invention .is one in which the water is normally maintained at the boiling temperature and is in constant circulation through the coolant chamber in the engine block, the flash tank and the water circulating passageway formed within the The condensing cycle will be explained later. 1

The principal purpose of the flash tank is to furnish a space of substantial vapor as it separates from the boiling liquid is of the utmost importance that the opening between the jacket chamber and the flash tank violent surging of the liquid results.

A separate water circulating passagewa is formed wholly y within the jacket chamber and is in unobstructed communication at both its upper and lower ends directly with the jacket returning to the jacket chamber. This action creates a comparatively cold and falling column of liquid while the engine water jacket proper forms a hot rising column. The result produces engine jacket, entrained vapor bubbles or, in other words, by vapor lift.

As a result of this circulation the returning liquid is thoroughly mixed with the hot liquid before reentering the jacket chamber, thus eliminating any chance of cold spots on the cylinder walls. In addition to this, the circulation of the liquid is important because it washes the vapor bubbles from the cylinder and head walls as they are formed, thus reducing the possibility of hot spots. The rate of circulation in the engine equipped with my, invention was found to be about 0.4 gallon per minute per horsepower. In my improved system a circulating pump is unnecessary.

volume providing a large liquid surface area for collecting the steam block by the customary aeoaeie coolant and the air passing through the radiator is much greater in the vapor phase cooling than it is in water cooling.

The principal means the boiling water is attained by permitting the steam vapor, formed from the boiling water, to pass through a down flow condenser, integrally formed within the system, vapor is reduced to a liquid. There it gives up,v as excess or waste heat, the latent heat of vaporization, plus a small amount of heat by chilling oi the condensed liquid, all of which condensate is then returned to the engine cooling jacket system. The liquid coolant in the at a level below the lower end of the passageway through the condenser core.

The importance of the use of a down flow primary condenser is apparent. The steam vapor flows downward thro'ughthe main core of the radiator and is not impeded by the condensate since the condensate also flows downward and away from the steam vapor by gravity. The uniflow of vapor.and condensate insures that only a very thin layer of condensate will be present in the radiator tubes. This offers much less impedance to heat flow than the thicker layer of liquid formed in a radiator where the flow of liquid opposes the flow oi the vapor.

A smaller section of the radiator joined to and adjacent the primary condenser acts in the capacity of a secondary or up-fiow condenser. It is provided at its uppermost end with an air vent and serves as a condenser to prevent the loss of vapor in the hot condensate. It also prevents the escape of vapor which may pass through some of the tubes which may have less air flow past them as might be caused by obstacles partially blocking the main core.

phase cooling for abstracting heat from The secondary condenser leaving '79 o! the 8'! tubes (2 tubes closed at the top between the tanks) in the first pass. through I f the radiator or the primary condenser. The out.-

chamber il oi the prilet from the condensate mary condenser is located so as to allow complete drainage or thecondensate through the return a duct 28.

. to the upper portion wherein the steam system is maintained the baffle wall 23 the relatively hot cylinder Referring to Fig. 1 and Fig. 2 of the drawings the numeral l0 indicates the engine frame to which is bolted or otherwise secured, the cylinder block H. A cylinder head [2 is attached to said method. A water jacket l3 surrounds the combustion chamber and a radiator generally indicated at M is connected with the water jacket.

The term "radiator in the present instance is applied in a general way as including a vapor chamber l5 to receive the incoming steam'vapor, the usual core I8 which operates as a primary down-flow condenser for cooling the steam vapors and returning the collected condensate, a condensate chamber I! to receive the condensate and return it to a return duct, a second core l8 which serves as a secondary or up-flow condenser, which serves to separate the vapor-and moisture from the entrapped air on its way to the air vent IS.

The double passradiator l4 shown inFigs. 1 and 2 was formed from standard automotive radiators, by altering them in thefollowing manner. The top of each tank wasslanted at one end as shown at 3| and 32 respectively. The

" slanting end wall of the smaller or secondary conway 22 formed wholly at both its upper and A flash tank 201s positioned above the water jacket l3 and has its interior in direct communication with the said jacket chamber. A duct 2| forms a connection from the top of the flash tank v of the vapor chamber I! 01 the radiator ll.

One of the principal features of my invention is the provision of a water circulating passagewithin the jacket chamber l3 so that it is in unobstructed communication lower ends directly with said jacket chamber l3. This passageway 22 is formed by integrally casting (or other equivalent construction) a baflie wall 23. within the jacket chamber [3 in spaced relation. between the hot outer surface 24 of the cylinder walls and the comparatively cooler inner surface 25 of the jacket chamber l3 and in the path of the con densate return from the condensate chamber I! through the return duct 26.- By so positioning in this location a down-flow water circulating passageway is formed within the .jacket chamber so that the cooler condensate return mingles with the returning liquid from the flash tank 20, while the hot liquid coolant flows up and around the outer surface 24 of the cylinder walls to the flash tank. This intermixing of the two. returning liquids tends to equalize their temperature and eliminate any possibility of the cool in direct contact with walls 24, thus avoiding cold spots in the system. It further accentuates the rate of circulation in' the thermo-syphon portion of the circulating system and is diagramatically shown by the arrows in Figs. 1 and 2.

In operation The cooling system is filled with water to the level as shown at 21. It is desirable that the water level be easily indicated by the use of pet cocks or a sight glass (not shown); The filler opening 28 is preferably located so that its top is at the desired water level. This opening 28 should be in communication with the water jacket chamber 13 through a passageway 29 below the water level 21 to prevent the escape of vapor while filling the engine jacket chamber. A plug 30 is provided to close and seal the opening 28.

For the proper functioning of the system disclosed herein it is imperative that the water level 21 in the engine jacket chamber be maintained at a point below the lowermost portion or the condensate chamber l1 and that the water level condensate return coming I in the chamber I] be below the radiator core.

When the engine is first started and the load is light orthe cooling system is cold there is naturally some air in the system. In order for any vapor phase cooling system to function safely and properly a volume of air equivalent to that displaced by the vapor must be vented from the systemas rapidly as displaced by the vapor.

The pressure ofair, when heated in the circulav tory. system, causes hot spots. and vapor lock to develop and if an excessive air pressure is built up it may be dangerous to-life and property should it .violently escape to the atmosphere. Hence in all systems of the type herein described it is imconnects with o-tubes denser.

portant that substantially all air be driven from the active part of the system.

The water is heated to the boiling point by the operation of the engine. The bubbles of water vapor break away from the hot surface of the cylinder and cylinder head, rising to the surface within the water jacket chamber and carry water with them. This causes a very definite and rapid in the air vent cap 19 is placed at the lower end of the single pass radiator section but above the condensate chamber H. The operating principle of all three types disclosed is identical.

While only the preferred form of my invention and three types of radiator or condenser constructions have been disclosed and described herein, I do not wish to be limited or 'restrictedto the downward circulation of water through the return passageway 22, provided within the jacket chamber [3.

The vapor which has risen to the water surface 21 is carried through the flash tank 20, and duct 2| to the vapor chamber i5 of the primary pass of the radiator l4. From this point the vapor passes through the down flow condenser I6 where the greater portion of the vapor, with. it entrapped air, condenses and the condensate enters the condensate chamber 11 to return through the return duct 26 to the water circulating passageway 22.

The air, with its small portion of entrained water vapor, seeks an exit to the atmosphere and passes up through the secondary condenser I8. During its passage through this condenser whatever small amount of water vapor it contains is given up due'to the cooling effect in its passage through the said condenser and the result i that nothing but air is left to escape through the vent l9. It is a well known principle of vapor phase cooling systems that the vapor will tend to travel towards the atmospheric vent, since it will move rapidly from the higher pressure in the engine towards the lower atmospheric pressure. The condensed water vapor from the condenser I8 joins with the condensate already in the condensate chamber l1 and thus returns to the circulating system along with the condensate from the primary condenser i 6. Thus it will be seen. that the secondary condenser l8 performs the very useful and important function of preventing the last trace of coolant vapor from escaping. This is an important function when using a highly volatile coolant such as alcohol. A pressure or valved vent capmay be used as an air vent to raise the engine temperature and pressure and also to increase the cooling capacity of-the system. The location of this air vent at the extreme up ermost part of the secondary condenser is most important as it 1 met be positioned in sucha place thatall air will be vented as displaced by the vapor. I In actual operation it has been found that the temperature out of the water jackets at point K (see Figs. 1 and 2) is that of the boiling point of the coolant. The temperature at point Y is never more than 2 F. below that at point X. From a consideration of the temperature of the condensate at point "2 it has been found that the rate of coolant circulation is about 0.4 gallon per minute per horse power and usually above this value in the particular size engine tested.

The radiator shown in Figs. 3 and 4 is a modiflcation of the construction shown in Figs. 1 and 2. The principal difference between these constructions is in the method of joining the two radiators and the positioning of the vent cap I9. In Figs. 3 and 4 the core 02 the secondary condenser is positioned directly behind'the core of the primary condenser and the vent cap I9 is located in the center and at the top of the secondary con- Figs'. 5 and 6 disclose a single pass radiator adapted to be used with my invention wherespecific details set forth and wish to reserve to myself any further embodiments, modifications and variations that may appear to those skilled in the art or fall within the scope of the appended claims. Any reference to specific data as to size, quantities, capacities, et cetera were used for illustration purposes only and are not to be construed to place a limitation on the principles disclosed in my invention.

Having fully described my invention, what I claim as new and desire to secure by United States Letters Patent is: 1. In a vapor cooling system for internal combustion engines including an engine cylinder cooling water jacket forming a coolant chamber, a flash tank positioned above and having its interior in direct communication wi said jacket chamber, a condenser, a connecting duct between the top of said flash tank and the'upper portion of said condenser, a water circulating passageway formed within said jacket chamber and being in unobstructed communication at both its upper and lower ends directly into said jacket chamber, a second connecting duct between the lower portion of said condenser and said passageway and an air vent adjacent the lower portion of the said condenser.

2. In a vapor cooling system for internal combustion engines including an engine cylinder cooling water jacket forming a coolant chamber, a double pass radiator, the first pass of said radiator forming a primary condenser, the second pass of said radiator forming a secondary condenser providing an air escape chamber in direct communication with said primary condenser, an

air vent in the uppermost portion of said secondary condenser, a flash tank positioned above and having its interior in direct communication with said jacket chamber, a connecting duct between the top of said flash tank and the upper portion of said primary condenser, a water circulating passageway formed within said jacket chamber and being in unobstructed communication at both its upper andlower ends directly into said jacket chamber, and a second connecting duct between the lower portion of said primary condenser and said passageway.

3. In a vapor cooling system for internal com bustion engines including an engine cylinder cooling water jacket forming a. coolant chamber, a flash tank positioned above and having its interior in direct communication with said jacket chamber, a condenser, a connecting duct between the top of said flash tank and the upper portion of. said condenser, a water circulating passageway formed within said jacket chamber and being in unobstructed communication at both its upper and lower ends directly into said jacket chamber, a second connecting duct leading from the lower portion of said condenser and entering said p ssageway approximately midway its length and an air vent adjacent the lower portion of said condenser.

W. HANNERS. 

